fix

com.unity.uiwidgets/Runtime/rendering/texture.cs

             _textureId = textureId;
         }
 
-        public int textureId {
+        public int? textureId {
             get { return _textureId; }
             set {
                 D.assert(value != null);
             }
         }
         
-        int _textureId;
+        int? _textureId;
 
         protected override bool sizedByParent {
             get { return true; }
             
             context.addLayer(new TextureLayer(
                 rect: Rect.fromLTWH(offset.dx, offset.dy, size.width, size.height),
-                textureId: _textureId
+                textureId: _textureId.Value
             ));
         }
     }

com.unity.uiwidgets/Runtime/widgets/basic.cs

             ImageRepeat repeat = ImageRepeat.noRepeat,
             Rect centerSlice = null,
             bool invertColors = false,
-            FilterMode filterMode = FilterMode.Bilinear
+            FilterMode filterMode = FilterMode.Bilinear ,
+            FilterQuality filterQuality = FilterQuality.low
+
         ) : base(key) {
             this.image = image;
             this.width = width;
             this.centerSlice = centerSlice;
             this.invertColors = invertColors;
             this.filterMode = filterMode;
+            this.filterQuality = filterQuality;
         }
 
         public readonly ui.Image image;
         public readonly ImageRepeat repeat;
         public readonly Rect centerSlice;
         public readonly bool invertColors;
+        public readonly FilterQuality filterQuality;
 
         public override RenderObject createRenderObject(BuildContext context) {
             return new RenderImage(
                 alignment: alignment,
                 repeat: repeat,
                 centerSlice: centerSlice,
-                invertColors: invertColors
-                // filterMode: filterMode
+                invertColors: invertColors,
+                filterQuality:  filterQuality
             );
         }
 
             renderImage.repeat = repeat;
             renderImage.centerSlice = centerSlice;
             renderImage.invertColors = invertColors;
-            // renderImage.filterMode = filterMode;
+            renderImage.filterQuality = filterQuality;
         }
 
         public override void debugFillProperties(DiagnosticPropertiesBuilder properties) {

com.unity.uiwidgets/Runtime/widgets/texture.cs

         //     }
         // }
 
-        public Texture(int textureId, Key key = null) : base(key: key) {
+        public Texture( Key key = null, int? textureId = null) : base(key: key) {
-            this.textureId = textureId;
+            if (textureId != null) {
+                this.textureId = textureId.Value;
+            }
         }
 
         public readonly int textureId;